为什么all行为与if这种情况不同？

In [1]: a = []

In [2]: if a and a[1]: # short circuiting -> no exception 
   ...:     pass
   ...: 

In [3]: all((a, a[0])) # a[0] is evaluated before the condition is evaluated -> exception
---------------------------------------------------------------------------
IndexError                                Traceback (most recent call last)
<ipython-input-3-a381b7aa45b3> in <module>()
----> 1 all((a, a[0]))

IndexError: list index out of range

回答

In [3]: all((a, a[0])) # a[0] is evaluated before the condition is evaluated -> exception